Y by
Round 2
1 Define the isolation index of real number
to be
, where
is the largest integer no greater than
, and
. For each positive integer
, find the maximum possible real number
such as there exists an infinite geometric sequence with common ratio
and isolation index of each term being at least
.
1 Define the isolation index of real number


![$[x]$](http://latex.artofproblemsolving.com/b/c/e/bceb7b14e55d33a8bca29b7863ad3cdae95afce4.png)

![$\{x\}=x-[x]$](http://latex.artofproblemsolving.com/6/1/0/61036a03415081af535bd57c408b7be79aae9458.png)




This post has been edited 2 times. Last edited by scls140511, Sep 8, 2024, 2:24 PM